<!DOCTYPE html>
<html>
<head>
  <script>
let testObject = { a:3 };
  </script>
</head>

<body>
  <div id="depth-1">
    <div id="depth-2">
      <div id="targetDiv"></div>
    </div>
    <div id="targetUncle">
      <div id="targetCousin"></div>
    </div>
  </div>
  <iframe src="iframe-content.html"></iframe>
</body>
</html>